Envelope Information

The ZMAIL Envelope Information is available for ZMAIL and IM Skins. It provides useful information before the message is decrypted, including:
• Date• From (the message sender)• To (the message recipient)• CC (additional message recipients, if any)• Subject• Fingerprint (optional)• Return Receipt Requested (optional)• Release Time (if set, at the end of the message)• Expiration Time (if set, at the end of the message)

The first four Envelope Information headers should match the corresponding email headers Date, From, To and Subject. The CC header is present by default but can be supressed for security purposes. The last four headers are optional; they are created by ZMAIL if requested by the sender, for message access control. Email addresses of additional recipients (Cc's / To's) will be shown to the recipient if desired by the sender (default), but only after the ZMAIL message is decrypted.

Fingerprint: (optional) The Fingerprint is the ZMAIL message visible digital signature. The Fingerprint provides a human-readable, simple, auditable record that the message was received exactly as it was sent, in addition to ZMAIL's internal authentication. Read more about the ZMAIL Fingerprint.

Return Receipt Requested: (optional) The sender may request a Return Receipt as a mandatory condition before the recipient can decrypt (read) the ZMAIL message. The Return Receipt informs the sender when (the time), where (the IP number), how (the browser or email agent identification), and by whom (the recipient's ZMAIL-authenticated name and email address) the message is decrypted, every time it is decrypted. If you wish to decline to provide the Return Receipt, do not decrypt the message. Read more about the ZMAIL Return Receipt. See a sample of the Return Receipt.

Release Time: (optional) The sender may define when the ZMAIL may be released for reading. The ZMAIL cannot be read before the Release Time shown at the bottom of the ZMAIL message. If no release time is shown, the message is available immediately. Read more about the ZMAIL Release Time.

Expiration Time: (optional) Provides "self-destructing email" function. The message can be decrypted and read before the Expiration Time shown at the bottom of the ZMAIL message. If no expiration time is shown, the message does not expire. Read more about the ZMAIL Expiration Time.

SECURITY: The Envelope Information that is visible before decryption is not secure. However, ZMAIL messages include a secure, authenticated, encrypted, and tamperproof copy of the Envelope Information, with all headers. You can rely on the digitally certified values of the Envelope Information that ZMAIL presents to you after the ZMAIL message is decrypted.

ANTI-SPAM: A [ZMAIL] tag is prefixed by ZMAIL to the visible Subject header, to help the recipient pre-sort spam and prioritize email before decryption. To be a valid ZMAIL it must have the [ZMAIL] tag AND pass the ZMAIL decryption test. The original Subject header is shown to the recipient after the ZMAIL message is decrypted.